Common Commercial Practice
This invention relates to an improved process of producing a sauce from a pome fruit, particularly apples.
The commercial production of apple sauce conventionally comprises the process steps of (1) washing the raw fruit, (2) manually assorting the raw fruit to remove fruit so severely blemished or misshapen as to preclude machine peeling, (3) assorting to size to accommodate machine peeling, (4) machine peeling and removal of core with its blossom end, (5) manual trimming to selectively remove blemishes (including surviving blossom ends) from the fruit, (6) slicing or chopping to promote rapid heat penetration during subsequent cooking (Apples and Apple Products, Smock & Neubert, page 302), (7) if sliced, the slices may optionally be subjected to a final manual inspection and selective surface area trimming, (8) cooking, and (9) finishing.
Two extremely costly factors are involved in the conventional process, namely the direct labor involved in the tedious selective trimming and the loss in yield of edible fruit through the operation of peeling and coring machines and, to an even greater extent, in the manual steps of selectively trimming defects from the surface of the peeled fruit and/or the sliced fruit. Similarly, the most wasteful steps from the standpoint of loss of yield are these same steps wherein mechanical peeling removes much edible tissue along with the skin, and coring removes a 1/2 or 5/8 inch cylindrical core extending diametrically through the fruit. Moreover, selective surface area trimming is inherently wasteful inasmuch as a manual trimmer is required to maintain a speed of operation which precludes the exercise of sufficient care to avoid removal of edible tissue surrounding the defect. Weight losses in mechanical peeling and coring steps normally represent from 30 to 40 percent of the weight of the fresh fruit (Commerical Fruit and Vegetable Products, W. V. Cruess, McGraw-Hill, 1938, p. 153).
The industry has been well aware of the losses involved in mechanical peeling and manual trimming, and has given attention to such proposals as chemical peeling with disappointing results. Even beyond problems of variable results occasioned by variations in variety and maturity of the raw fruit were two particularly troublesome impediments.
First, while a distinct saving in waste was realized in the chemical peeling step itself (as compared to mechanical peeling), the saving proved to be a false economy, especially with low quality lots of fruit, for it did not survive the subsequent steps in the process. When chemically peeled fruit with a high level of defects such as bruises or hail marks reached the subsequent manual trimming step, the fact that surface blemishes were much more evident caused the trimming workers to remove more tissue to the extent that a net loss was encountered.
Thus, chemical peeling did not significantly reduce the waste in coring (removal of the calyx end by coring or extremely deep cutting remained necessary) and increased the waste incurred in the step of selective surface area (manual) trimming.
Secondly, chemical peeling was ineffective to remove deepseated vestigial stamens, particularly in fruit varieties characterized by a deep calyx.
While the finisher commonly employed in presently accepted processes is effective to remove hard tissue such as seeds or the carpel tissue (commonly called "seed cell") of the core, as well as the hard tissue of flesh defects, it does not remove fruit portions which are visually objectionable but are of such small size or soft character as to pass through the screen of the finisher. Prominent among these last-mentioned objectionable portions is the aforementioned blossom or calyx end of the fruit. This blossom end includes a plurality of short, thin filamentary organs which are the vestigial stamens of the original blossom. While these vestigial organs are harmless and virtually indiscernible insofar as taste or eating qualities are concerned, they become extremely objectionable by virtue of the fact that their configuration and black color resemble that of an insect member, such as a fly leg.
While normal coring of the fruit removes a cylindrical segment from the fruit which comprises the core axis including the stem and the blossom ends, the effectiveness of this removal depends upon the accuracy of the orientation of the fruit in the machine during the coring operation. Whether this orientation is done manually by the machine operator or mechanically by the coring machine itself, it is subject to error which often results in the removal of a cylindrical segment which is not coaxial with the core and hence does not include the blossom end with the removed segment. Consequently, it is necessary to maintain sufficient manual trimming capacity following a coring operation not only to trim defects from other areas of the fruit but also to detect and selectively trim those blossom ends remaining on the fruit as a result of misalignment in the coring apparatus. In practice, this volume is sufficiently high to present a significant labor demand. When it is realized that a single blossom end includes approximately 20 vestigial stamens, it can be seen that the passage of one blossom end through the coring and subsequent visual inspection and selective hand trimming steps, and thus ultimately into the product, can downgrade a considerable volume of product from the standpoint of its acceptability to the consumer.
In addition to the matter of consumer acceptance, the U.S. Department of Agriculture scoring system for grading of apple sauce prescribes a maximum of three blossom ends (i.e., vestigial stamens) per 15 oz. of sauce for Grade A, and five blossom ends for Grade B. Hence, otherwise good quality sauce can be forced into a poor grade by this defect alone.
A further problem in currently practiced methods of sauce production is the loss of usable fruit flesh incurred in mechanical coring. Studies conducted on a pilot plant scale reveal that 77% of the mechanically removed core consists of usable fruit tissue. This tissue, if recoverable, amounts to approximately 10% of the total fruit weight. This invention permits the use of the whole uncored fruit without otherwise attendant problems of increased hand trimming requirements.
Another significant loss of flesh is inherent in the mechanical peeling of fruit by machine. Even with careful adjustment of the depth of cut of the peeling knife, losses of as high as 30% are incurred, particularly in the smaller fruit sizes. This inventor's initial experimental work with lye peeling of apples was somewhat disappointing inasmuch as the saving in weight loss was partially offset by the fact that more trimmable defects survive lye peeling than do mechanical peeling, hence the lye peeled fruit suffers correspondingly greater loss at the hands of hand trimmers under present preparation processes. Weight loss studies indicate that initial savings of from 7.8% to as high as 25.4% attainable by lye peeling were offset by as much as a 3.2% increase in loss at the hands of manual trimmers. The present invention enables the use of lye peeling without subsequent hand trimming, and reduces the loss after peeling to 1.1%.
Even more apparent than the foregoing problems in existing techniques is that of the direct labor involved in operation of coring and peeling machines and in visually selecting and manually trimming the surface of the fruit thus prepared. Typical of plant operations is that of a plant comprising 32 peeling and coring machines wherein the preparation (i.e., peeling, coring, inspecting and trimming) of the fruit requires the services of 168 persons.